1. Field of the Invention
The invention relates to a flashlight, more particularly to a flashlight having a waterproof switch device mounted on a rear end thereof.
2. Description of the Related Art
FIGS. 1 and 2 illustrate a flashlight disclosed in U.S. Pat. No. 5,752,764. As shown, a barrel body 8 has a front annular end 81 and a rear annular end 82 in a longitudinal direction, and a battery (not shown) received in the barrel body 8 such that an electrode thereof is proximate to the rear annular end 82. A switch device is mounted on the rear annular end 82 for switching on and off a bulb 83 mounted at the front annular end 81. The switch device includes a conductive coupling member 20, a conductive spring member 25, an insulative first retaining member 26, a contact member 24, an actuating plunger 21, a second retaining member 22, and a cap member 23. The coupling member 20 has a front annular wall 201 adapted to be moved in the longitudinal direction relative to the rear annular end 82 of the barrel body 8 and adapted to engage the rear annular end 82 to establish an electric connection therebetween, a rear annular wall 202, and a middle annular portion interposed between the front and rear annular walls 201, 202. The spring member 25 is retained in the coupling member 20 and is insulated therefrom by the first retaining member 26 in such a manner that a front section 251 thereof extends outwardly of the coupling member 20 so as to be brought into contact with the electrode. The contact member 24 is sleeved around the second retaining member 22, and the assembly of the members 22, 24 is disposed in the middle portion of the coupling member 20 such that contact ends 241 of the contact member 24 are located proximate to a rear section 252 of the spring member 25. The actuating plunger 21 is disposed to be movable relative to the coupling member 20 in an axial direction, and has a front actuating portion 212 secured to the rear section 252 of the spring member 25 to electrically connect and disconnect the contact ends 241 to and from the rear section 252, and a depressible portion 211 that extends rearwardly and outwardly of the second retaining member 22. The cap member 23 includes a cap portion 230 mounted on the rear annular end 202 of the coupling member 20, and has a socket portion 232 that extends forwardly in the axial direction so as to be plugged therein by the depressible portion 211 of the actuating plunger 21.
Some of the disadvantages of the aforesaid conventional switch device are as follows:
The second retaining member 22 is retained in the coupling member 20 by virtue of friction force that is applied by a ring 235, and the depressible portion 211 extends through the second retaining member 22. Thus, sliding movement of the depressible portion 211 may eventually result in disengagement of the ring 235 and the second retaining member 22 relative to the coupling member 20 after long term use.
An annular clearance is formed between the cap portion 230 and the rear annular end 202 of the coupling member 30 after the assembly, thereby resulting in poor waterproof effect for the conventional switch device.